1. Field of the Invention
The general inventive concept relates to a switching amplifier and an audio apparatus including the same, and more particularly, to a switching amplifier which is capable of operating an amplifier consisting of depletion-type transistors by using a single power port and an audio apparatus including the same.
2. Description of the Related Art
An audio apparatus refers to an apparatus which outputs an audio signal recorded in a form of an electrical signal, and includes an amplifier for amplifying the audio signal. Such amplifier includes a transistor for amplifying the audio signal, and is divided into various types according to a type and arrangement of the transistor.
In the related art, a P-N type switching amplifier where a P-type transistor is arranged on an upper side and an N-type transistor is arranged in a lower side and an N-N type switching amplifier where N-type transistors are arranged on both sides have been commonly used.
Such P-N type switching amplifier and N-N type switching amplifier are not turned on when a Vgs of each of the transistors is 0V, and thus, do not cause any problem even though two transistors are connected by a single power port. To be specific, there is no possibility that two transistors are turned on simultaneously even though two transistors are connected in series, and thus, it is possible to operate two transistors by a single power port.
Recently, in order to improve performance, a gallium nitride (GaN) transistor which is turned on even when a Vgs voltage is 0V is used to embody a switching amplifier. However, the GaN transistor may operate even when the Vgs voltage is 0V, and thus, when a switching amplifier is formed of a circuit which is the same as an existing circuit, two transistors may be turned on simultaneously. As the result, there has been a problem that a positive (+) power terminal and a negative (−) power terminal are shorted out when the GaN transistors connected in series are turned on simultaneously.